The Internal Revenue Service (IRS) was an American government organization that collected taxes.
Gary Seven had forged IRS identification. (ST novel: The Rise and Fall of Khan Noonien Singh, Volume 1)
A Ferengi storyteller once commented that Quark greeted his relatives with about the same glee as an American greeted a tax audit from the IRS. (DS9 - Strange New Worlds 9 short story: "The Last Tree on Ferenginar: A Ferengi Fable From the Future")